Right radical is 'branch' (支), here used in its literal meaning of 'hand
holding a bamboo stick'.
Left radical is 'edible plants in a food vessel', used for its sound of 'CHUU'.
This character originally meant 'instrument resembling food vessel which makes
the CHUU sound when struck with a bamboo stick'. Henshall suggests taking the
top right element as 'samurai', (士), and as a mnemonic:
'Samurai wields branch, using food pot as drum.'